Insulin Therapy & Type 1 Diabetes Mellitus – Review Flashcards

Question-and-Answer cards covering pharmacology, dosing, mixing, adjustment, and hypoglycemia management for insulin therapy in Type 1 Diabetes.

What are the two physiologic categories of insulin replacement?

Basal (fasting-state suppression of hepatic glucose, ~50 % of TDD) and Prandial/Bolus (meal-time coverage, ~50 % of TDD).

Which generic insulins are classified as rapid-acting?

Aspart, Lispro, and Glulisine.

Typical onset, peak, and duration for rapid-acting analogs (aspart, lispro, glulisine)?

Onset 10-30 min, peak 1-2 h, duration 3-5 h.

When should rapid-acting insulin be injected in relation to a meal?

5–15 minutes before (or immediately after) eating.

Can rapid-acting analogs be mixed with NPH?

Yes (draw rapid/clear first, then NPH/cloudy).

Which insulin has an ultra-short formulation called Fiasp or Lyumjev?

Insulin Aspart (Fiasp) or Insulin Lispro (Lyumjev).

What are the generic names of short-acting ‘regular’ insulin?

Regular insulin (Humulin R, Novolin R).

Onset-peak-duration profile for U-100 regular insulin?

Onset 30-60 min, peak 2-3 h, duration 6-8 h.

Key counseling point for regular insulin timing with meals

Inject 30 minutes before eating.

Which concentrated regular insulin is five times stronger than U-100?

Humulin R U-500.

Who typically needs U-500 insulin?

Patients with severe insulin resistance (often >200 units/day).

List the intermediate-acting insulin used for basal coverage.

NPH insulin (Humulin N, Novolin N).

Why must NPH vials/pens be rolled before use?

It is a suspension that must be gently mixed to resuspend insulin crystals.

Typical dosing frequency for NPH in type 1 diabetes

Twice daily (before breakfast and dinner/bedtime).

Generic names of long-acting basal analogs

Detemir, Glargine, and Degludec.

Which long-acting insulin has no pronounced peak and ~24 h duration?

Glargine U-100 (Lantus, Basaglar, Semglee, Rezvoglar).

Which basal insulin can provide >42 h duration and comes as U-100 or U-200?

Degludec (Tresiba).

Only basal insulin that can be premixed with a rapid insulin (Ryzodeg)?

Degludec (70 % degludec / 30 % aspart).

Conversion rule when switching NPH twice daily to Glargine U-100

Reduce the calculated NPH total by 20 % and give once daily glargine.

Which insulin cannot be mixed with any other insulin in the same syringe?

Long/ultra-long analogs (Detemir, Glargine, Degludec).

What is the ‘clear before cloudy’ rule?

Draw rapid/regular (clear) insulin into syringe first, then NPH (cloudy).

Rank subcutaneous injection sites from fastest to slowest absorption.

Abdomen > Arm > Thigh (resting) > Buttocks.

Two lifestyle factors that speed insulin absorption

Hot temperature and exercise within 1 hour of injection.

How does smoking affect insulin absorption?

It slows absorption.

Renal dose adjustment guideline when CrCL 10-50 mL/min

Consider 25 % dose reduction.

Which medications mask adrenergic symptoms of hypoglycemia?

Beta-adrenergic blockers.

Name three drug classes that decrease insulin effectiveness.

Systemic corticosteroids, thiazide diuretics, nicotinic acid.

Common adverse effects of insulin therapy (name four).

Hypoglycemia, weight gain, lipodystrophy (lipo-hypertrophy/atrophy), hypokalemia.

Define Level 1 hypoglycemia (ADA).

Blood glucose <70 mg/dL but ≥54 mg/dL.

Define Level 2 hypoglycemia.

Blood glucose <54 mg/dL (moderate).

Define Level 3 hypoglycemia.

Severe event with altered mental/physical status requiring assistance.

Give three adrenergic (early) symptoms of hypoglycemia.

Palpitations, sweating, tremors (also anxiety, irritability, pallor).

Give three neuroglycopenic (late) symptoms of hypoglycemia.

Confusion, slurred speech, seizures (also disorientation, unconsciousness).

Outline the ‘15/15 rule’ for mild-moderate hypoglycemia.

Take 15 g fast carbs, wait 15 min, re-check BG; repeat if still ≤70 mg/dL.

List three examples of 15 g fast carbohydrates.

4 oz juice, 3-4 glucose tablets, 1 Tbsp sugar/jelly (also ½ can regular soda, 7-8 candy pieces).

First-line emergency treatment for Level 3 hypoglycemia at home

Administer glucagon (IM/SC/IN) or IV dextrose if in medical setting.

Name two ready-to-use glucagon products that do not require reconstitution.

Gvoke PFS/HypoPen (SC) and Baqsimi (intranasal powder).

Standard adult SC/IM dose for traditional glucagon injection

1 mg (0.5 mg for children <45 lb).

What precaution should be taken after giving glucagon due to emesis risk?

Position patient on their side to prevent aspiration.

Describe the ‘honeymoon phase’ in type 1 diabetes.

Transient period after diagnosis where remaining β-cells produce some insulin, lowering exogenous insulin needs for weeks-months.

Differentiate Dawn phenomenon vs Somogyi effect mechanism.

Dawn: early-morning hormone surge causes hyperglycemia; Somogyi: nocturnal hypoglycemia triggers rebound hyperglycemia.

2–3 am BG high: which phenomenon and adjustment?

Dawn phenomenon; increase bedtime basal or shift dose later, avoid bedtime carbs.

2–3 am BG low: which phenomenon and adjustment?

Somogyi effect; decrease bedtime basal or add bedtime snack.

Standard initial total daily insulin dose (TDD) for type 1 diabetes (class value).

0.5 units / kg / day (conservative 0.2–0.4 possible).

How is TDD split in a four-injection basal-bolus regimen?

50 % basal once daily; 50 % prandial divided equally before three meals.

Basic split for a two-injection NPH/Regular regimen.

2/3 of TDD before breakfast (2/3 NPH, 1/3 rapid/regular) and 1/3 before dinner (½ NPH, ½ rapid/regular).

What is the Rule of 500?

500 ÷ TDD = grams of carbohydrate covered by 1 unit of rapid insulin (use 450 for regular insulin).

What is the Rule of 1800?

1800 ÷ TDD = mg/dL BG drop produced by 1 unit of rapid insulin (use 1500 for regular).

Formula for total meal bolus using flexible dosing

Total Bolus = Carb Coverage + Correction Factor.

In flexible bolus dosing, what must be subtracted from total carbohydrates on a food label?

Dietary fiber grams (to obtain net carbs).

General ‘rule of thumb’ BG reduction per 1 unit insulin in type 1 DM when adjusting doses

≈ 50 mg/dL per unit.

Suggested incremental change when adjusting insulin doses

Increase or decrease by 10 % or 1–2 units every ≥3 days, monitoring BG closely.

Stepwise logic to decide which insulin dose to change

Identify out-of-range BG, ‘look backward’ to preceding insulin dose that affects that reading, adjust that dose.

Conversion rule when switching most insulins (except noted cases)

Unit-to-unit (1 : 1) conversion.

Time interval recommended between dose changes when initiating Degludec

Adjust no more often than every 3–4 days.

Which basal insulin requires 5 days to reach max effect and is pen-only?

Glargine U-300 (Toujeo).

Two primary advantages of insulin pump therapy

Most physiologic insulin delivery (basal + bolus) and lower hypoglycemia risk.

Main disadvantages of insulin pump therapy

Higher cost and need for extensive patient education/training.

Sliding-scale insulin in hospital: proactive or reactive?

Reactive; treats hyperglycemia after it occurs, not preferred long term.

Three factors that increase hypoglycemia risk in type 1 diabetes

Older age, longer diabetes duration, exercise (also delayed meals, alcohol, prior episodes).

Why should glucagon be prescribed to all patients on insulin?

Provides emergency treatment option for severe hypoglycemia when patient cannot self-treat.

What OTC premixed insulins are available?

Humulin 70/30, Novolin 70/30 (NPH/Regular mixtures).

Name two advantages of premixed insulin products.

Fewer injections and no need to calculate or mix individual components.

Primary disadvantage of premixed fixed-ratio insulins

Less flexible—cannot adjust basal without altering prandial dose; higher hypoglycemia risk.

Which insulins are available over-the-counter in the United States?

Regular U-100 and NPH (human insulins) and their premixed 70/30 products.

How do fluoroquinolones affect glycemia?

They can cause hypoglycemia or hyperglycemia (dysglycemia).

What is lipohypertrophy and how is it prevented?

Thickening of subcutaneous fat at injection sites; prevent by rotating injection sites.